delivery to aol recipients has been delayed - error

I'm getting the aol delivery error when people send mail from my domain to aol.

This is an automatically generated Delivery Status Notification.

THIS IS A WARNING MESSAGE ONLY.

YOU DO NOT NEED TO RESEND YOUR MESSAGE.

Delivery to the following recipients has been delayed.

       xxx@aol.com

I've done some searching and haven't found any clear answer about this one. I'm running E2K3.
thanks.

im having the same error, except mine dont say that "i do not" need to resend, mine say it has been rejected.......

NVM i found my answer, i do not have a reverse DNS entry for the MX record, and aol treats you like span if one is not set-up, check dnsstuff.com to see if you have one.......GL

thanks.
which test did you do?

MCI created the reverse DNS PTR records for my domain over a week ago, but I'm still getting the same problem. I assume they created a record for my MX record- is that correct?

Does http://www.dnsreport.com/ now show a PASS for the Reverse DNS entries for MX records test ?

Hi Nick-
yes, it shows a PASS.

Just got a response from MCI. My mail server is resolving to a different IP- not sure why. He went ahead and added a PTR record for that IP.
When I PING my mail server's dns name it gives the correct IP.
So why is my connection from my mail server coming from a different IP?

goofy nat setting on your firewall would be my guess.  Was it at least an IP address in your range?

my router is managed by mci. the ip is registered to uunet, which i think is an mci parnter (?).
i have a dual nic server that is my mail server, so maybe it's originating from the wrong interface?

Well you can test that. Send a mail from it to a hotmail address and view the email headers when you receive it in hotmail. One of the first lines will be a Received: from mx1.domain.co.uk ([194.nn.nn.nn]) type format...

I just had the owner of my IP address setup my PTR record. It was a completely different company to my ISP, but they set it up very quickly for us. And immediately afterwards, aol emails started working.

I did some tests via manual telnet SMTP on my mail gateway.

First, I used nslookup to get an aol MX mailserver... mailin-01.mx.aol.com
ie... nslookup
set type=mx
aol.com
exit

Our conversations went like this:
(Blue writing is my commands)
(Red writing is aol responses)

(the "peer name unknown" is the telling part)

----------- BEFORE PTR RECORD SET UP ---------------
----------- AFTER  PTR RECORD SET UP ---------------

Does your NSLOOKUP work and do you get the "peer name unknown" when you say 'EHLO'?

Hi Nick-
thanks for the response.
my nslookup does work and i don't get the "peer name unknown".  though i do get a syntax error when i do the "mail from:<me@mydomain.com>" command.

MCI created a pointer to the IP that my mail server is supposedly originating from. So I'm not getting the AOL error anymore. I just can't figure out why the IP changed and why it's not originating from my external IP anymore.

How many NIC's do you have on the E2K3 server. Is that connected directly to the internet (ie no smarthosts, etc.)?

Check your routing... 'ROUTE PRINT'